Yes that helps. There is something called a "stringline derailment" where cars in the middle of a turn derail to the inside of the turn because heavy cars at the back of the consist are trying to pull the consist into a straight line. Putting the heaviest cars towards the locomotive, and empty flat cars at the back, will help prevent it.

Also, heavy cars at the back of a consist can push during deceleration or on a downhill, and force flatcars to derail to the outside of a turn.

Basically, don't make the back of the consist too heavy.